I put a 582 on my Gemini I put the battery behind the seat to compensate for c of g, it flew fine no issues it started out pitch unstable due to a high mounted exhaust and about 8 kilo's of bog in the nose of the pod amongst other things from a previous owner. I was part of the pitch unstable scenario with Tony Hayes and I flew most of the troubled Gemini Thrusters he was working on, they were a nice aeroplane if left in original design